We calculate the angular power spectrum of galaxies selected from the Sloan Digital Sky Survey ( SDSS ) Data Release 7 ( DR7 ) by using a quadratic estimation method with KL-compression .
The primary data sample includes over 18 million galaxies covering more than 5,700 square degrees after masking areas with bright objects , reddening greater than 0.2 magnitudes , and seeing of more than 1.5 arcseconds .
We test for systematic effects by calculating the angular power spectrum by SDSS stripe and find that these measurements are minimally affected by seeing and reddening .
We calculate the angular power spectrum for \ell \leq 200 multipoles by using 40 bandpowers for the full sample , and \ell \leq 1000 multipoles using 50 bandpowers for individual stripes .
We also calculate the angular power spectrum for this sample separated into 3 magnitude bins with mean redshifts of z = 0.171 , z = 0.217 , and z = 0.261 to examine the evolution of the angular power spectrum .
We determine the theoretical linear angular power spectrum by projecting the 3D power spectrum to two dimensions for a basic comparison to our observational results .
By minimizing the \chi ^ { 2 } fit between these data and the theoretical linear angular power spectrum we measure a loosely-constrained fit of \Omega _ { m } = 0.31 ^ { +0.18 } _ { -0.11 } with a linear bias of b = 0.94 \pm 0.04 .